This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The major goal of our research activities is to advance understanding of the fundamental molecular mechanisms involved in the formation of dental enamel. We postulate that such understanding will lead to the future development of biomimetic strategies for the creation of enamel-like mineral materials. We focus on two areas: 1. The structure and function of enamel extracellular matrix components. 2) The function and mechanism of action of enamel proteinases MMP-20 (enamelysin) and KLK-4. Our goals are: ( project #1) to identify the nature of the interactions which define protein self-assembly in solution and the nanosphere matrix architecture, at the molecular level, to define at the molecular level the ultrastructural architecture of amelogenin-based matrices formed in vitro, to characterize apatite and octacalcium phosphate crystal growth, morphology and orientation within synthetic amelogenin gel matrices in the absence and presence of the non-amelogenins. To characterize the effects of amelogenin and non-amelogenins on apatite and octacalcium crystal growth morphology in solution. (project # 2) : To investigate the action of recombinant MMP-20 and KLK-4 on recombinant enamel proteins amelogenin.